Nail



F L. MACKENZIE.

NAIL.

APPLICATION FILEDSEPTA. 1917.

1,400,75 Patented Deo. 20, 19ZL FRED L. MACKENZIE, 0F BEVERZY,MASSACHUSETTS, ASSIGrhTB, BY MESNE .PiSSIGrhT- MENTS, TO 'UNITED SHOEMACHINERY A CORFORATIN 0F NEU] CORPRAE'ION, OF PATERSON, ll'llllERSI'EY,

NAEL.

@riginal application led ctober la, wie, Serial llo. 866,675. llvded andthis application Serial No. 189,428.

teinher l, 1917.

To all 107mmt may concern:

Be it known that l, FRED L. MACHEN/zin, a citizen of the United States,residing at Beverly, in the county of Essex and State ot hlassachusetts,have invented certain lmprovements in Nails, ot which the followingdescription, in connection with the accompanying drawings, is aspecification, like reference characters on the drawings indieating likeparts in the several iigures.

rlhis invention relates to tastenings and is illustrated as embodied infastenings of the type commonly termed string nailsl String nails areused tor the most part in shoe nailing or tacking machines and theordinary nail string supplied for such machines comprises a series ofnails formed in one integral string, usually with the pointV or end oi'the shank oi"- one nail connected to some part of the head ot' the nextnail. ln use the nail string is carried upon a reel and the nailingmachine is provided with means for engaging the'head oi' the nail to bedriven, feeding it into the throat or" the machine, and severing it fromthe string. rihe mechanism ot the machine for handling these nails isvery simple, and tor many purposes it would be desirable ,to employstring nails if they could be manufactured economically, and could beprovided with heads sufficient to prevent their being pulled through theparts which are to be secured together by them.

It is advantageous trom the commercial standpoint to form the nails ornail strings from sheet metal, and it the nail is to be used as apermanent fastening, it is important that it have formed thereon aconsiderable head projecting to one or both sides et' the shank in theplane of the strip, since it is obviously not possible without a swaging operation to cause the head to project over the tlat sides of thenail shank. A convenient, economical and practical method oi"inanutacturing` nail strings comprising such nails is described andclaimed in lietters Patent No. 1,241,868, granted ct. 2, 1917, on myco-pending application Ser. No. 866,675, tiled @et 1e, 1914, of whichthis application is a division.

An object ot the present invention is to provide an improved nailcapable of being Specification of Letters Patent.

Patented Dec. 2th, 1921i.

`iled Sepmanufactured in union with other nails ot the same kind in anail string and having a head ot much greater holding` power than theordinary string nail head, and an important tea-ture of the inventionresides in a string nail having a hook-shaped head ot an improved form.

Figure 1 illustrates a pair of nail strings constituting an embodimentof the invention and illustrating their manu-facture from a. singlestrip; and 2 illustrates a nail as severed from the nail string ci Fig.l.

Each of the nail units or" the string shown in the drawing comprises ashank 2 having a straight edge fl, which is the edge of the ribbon orstrip ot sheet metal from which the nail string is cut, an inclined edge6 and a head 8, which is ot curved hook shape upon its under side, thedownwardly projecting barb or point l() ot the head acting to increaseconsiderably the holding power of the head. The curve is found advisablebecause of practical ditliculties in the manufacture of a sharp corneredoutline, and the .sides of the curve also reinforce the head and keep itfrom breaking off readily. lt will be noticed that the head isunbalanced e., it extends to one side only of the shank. lt is thereforenecessary that it drive straight in order to avoid lateral pressure ordraw on the shank which would loosen it in its hole. ln order to obtainthis advantage the barb 10 is preferably beveled slightly at 11 upon itsouter edge to form a symmetrical point and to compensate somewhat torthe tendency ot the curved inner edge to turn out the point or draw thehead in the driving operation.

Having thusdescribed my invention, what l claim as new and desire tosecure by lietters Patent of the United States is* 1. A nail formed ofsheet metal, having a shank and an unbalanced head lying in the plane ofthe shank, said head having a depending projection on its under side atits extremity, the projection having a lower surface extendingtransversly of the Vnail shank and having faces inclined toward eachther in the plane of the shank.

2. A nail having a shank and a head, said head having a dependingprojection on its underside at a point remote from the shank,

Bil

its underside at its extremity, the lower surface of the projectionbeing attened and extending in :t direction substantially at rightangles to the shank of the nail. 10

In testimony whereof I have signed my name to this specification.

FRED L. MACKENZIE.

